Field of the Invention
The present invention relates to a thermal energy recovery device and a start-up method thereof.
Description of the Related Art
Conventionally, a thermal energy recovery device for recovering power from a heating medium such as an exhaust gas discharged from various facilities of a factory is known. For example, JP 2014-47632 A discloses a power generating device (thermal energy recovery device) including an evaporator for heating a working medium by a heating medium supplied from an external heat source, a preheater for heating the working medium before flowing into the evaporator by the heating medium flowing out of the evaporator, an expander for expanding the working medium flowing out of the evaporator, a generator connected to the expander, a condenser for condensing the working medium flowing out of the expander, a working medium pump for sending the working medium condensed by the condenser to the preheater, and a circulating flow path for connecting the preheater, the evaporator, the expander, the condenser, and the pump.
In the thermal energy recovery device described in the above JP 2014-47632 A, in a case where steam (a medium in a gas phase) is supplied to the evaporator as the heating medium, it is concerned that the temperature of the evaporator rises suddenly when the operation of the device is started and thereby thermal stress generated in the evaporator is increased rapidly. Concretely, before the operation of the device is started, while the temperature of the evaporator is relatively low, the thermal energy that a heating medium in a gas phase such as steam has is very large, and therefore if the high temperature heating medium in a gas phase flows into the evaporator when the operation is started, it is feared that the temperature of the evaporator rises suddenly.